A record quiet start to the 2010 Northern Hemisphere tropical cyclone season

By: Dr. Jeff Masters , 3:42 PM GMT on August 12, 2010

Share this Blog
4
+

The remnants of Tropical Depression Five have re-organized this morning, and the storm is pounding Southeast Louisiana with heavy rains. Radar imagery out of New Orleans shows that the remains of TD 5 have have formed some respectable low-level spiral bands that have brought heavy rains in excess of five inches in some areas. However, with the circulation center now moving over land, not much further development can occur.


Figure 1. Morning radar image of TD Five's remains.

Why so quiet in the Atlantic?
The Tropical Atlantic is quiet, and there are no threat areas to discuss today. The Invest 93 system we were tracking has been destroyed by dry air and wind shear. There are a couple of long-range threats suggested by some of the models--the GFS model predicts a tropical depression could form off the coast of Mississippi six days from now, and the NOGAPS model thinks something could get going in the Gulf of Mexico's Bay of Campeche seven days from now. Neither of these possibilities are worthy of concern at present. Overall, it's been a surprisingly quiet August, considering the pre-season predictions of a hyperactive season. According the National Hurricane Center, this hurricane season has been exactly average so far. There have been three named storms and one hurricane as of August 12. The average date of formation of the third named storm is August 13. One hurricane typically forms by August 10. One reason for this year's inactivity may be an unusual number of upper-level low pressure systems that have paraded across the tropical Atlantic. These lows, also called Tropical Upper Tropospheric Trough (TUTT) lows, tend to bring high wind shear that inhibits tropical cyclone formation. The other major factor appears to be that vertical instability has been unusually low in the Atlantic over the past month. Instability is measured as the difference in temperature between the surface and the top of the troposphere (the highest altitude that thunderstorm tops can penetrate to.) If the surface is very warm and the top of the troposphere is cold, an unstable atmosphere results, which helps to enhance thunderstorm updrafts and promote hurricane development. Since SSTs in the Atlantic are at record highs, enhancing instability, something else must be going on. Dry air can act to reduce instability, and it appears that an unusually dry atmosphere over the Atlantic this month is responsible for the lack of instability.


Figure 2. Vertical instability (in °C) over the Caribbean (left) and tropical Atlantic between the Lesser Antilles Islands and coast of Africa (right) in 2010. Normal instability is the black line, and this year's instability levels are in blue. The atmosphere became much more stable than normal in both regions at the end of July. This lack of instability also extends to the Gulf of Mexico and North Atlantic Ocean between Europe and North America, as well as the Western Pacific east of the Philippines, and the South Indian Ocean. Image credit: NOAA/CIRA.

A record quiet start to the 2010 tropical cyclone season in the Northern Hemisphere
What is really odd about this year, though, is the lack of tropical cyclone activity across the entire Northern Hemisphere. Usually, if one ocean basin is experiencing a quiet season, one of the other ocean basins is going bonkers. That is not the case this year. Over in the Eastern Pacific, there have been five named storms and two hurricanes. The average is seven named storms and four hurricanes for this point in the season. This year's quiet season is not too surprising, since there is a moderate La Niña event underway, and La Niña conditions usually supresses Eastern Pacific hurricane activity. But over in the Western Pacific, which usually generates more tropical cyclones than any ocean basin on Earth, it has been a near-record quiet season. Just four named storms have occurred in the West Pacific this year, and the average for this date is eleven. Only one typhoon season has had fewer named storms this late in the season--1998, with just three. The total number of named storms in the Northern Hemisphere thus far this year is fifteen, which is the fewest since reliable records began in 1948. Second place belongs to 1983 and 1957, with eighteen named storms. According to an email I received from NOAA hurricane researcher Gabe Vecchi, the lack of tropical cyclones so far this year in the Northern Hemisphere is between a 1-in-80 and 1-in-100 year event.

So, what is causing this quiet tropical cyclone season? One possibility is that since Northern Hemisphere land areas have heated up to record temperatures this summer, this has created strong rising motion over the continents. This rising motion must be compensated by strong sinking motion over the adjacent oceans in order to conserve mass. Sinking air causes drying and an increase in stability. Another possibility is that the unusual jet stream configuration that is responsible for the Russia heat wave and record flooding in Pakistan is also bringing dry, stable air to the Northern Hemisphere's tropical cyclone breeding grounds. It is also possible that climate change is causing the reduction in tropical cyclone activity, for a variety of complex reasons. Computer simulations of a future warmer climate generally show a reduction in global number of tropical cyclones (though the strongest storms get stronger), and it is possible we are seeing a preview of that future climate. Or, this year's quietness may simply be natural variability. It will be interesting to see when the Russian heat wave breaks if vertical instability over the Atlantic increases back to normal levels. Current forecasts from the GFS and ECMWF models project the Russian heat wave to break late next week.

Moscow's air remains clear; coolest temperatures in two weeks
Moscow's winds remained favorable for keeping smoke away from the city today, and temperatures "cooled" to at Moscow's Domodedovo airport to 33°C (91°F)--the lowest maximum temperature since a high of 32°C (90°F) was recorded on July 30. Moscow's airport has reached a maximum temperature of 30°C (86°F) or higher for 35 consecutive days now (at Moscow's official observing site, the Moscow Observatory, this string is 30 days.) Moscow's average high temperature for August 12 is 20°C (68°F). Moscow's high temperatures have averaged 15°C (27°F) above average so far this August--a truly extraordinary anomaly for a country so famous for its notorious cold weather. The latest forecast for Moscow calls for high temperatures of 30 - 33°C (86 - 91°F) Thursday through Monday. This is still 23°F above normal, but will be a welcome change from the extreme heat of the past two weeks. Long range forecasts from the ECMWF and GFS models continue to suggest that a series of troughs of low pressure will begin to attack the ridge of high pressure anchored over Russia beginning on Wednesday, bringing cooler temperatures just 5°C (8°F) above average to Russia late next week. By ten days from now, the ECMWF model shows a strong trough of low pressure over Moscow, and a end to the Great Russian Heat Wave of 2010.

Next update
I'll have an update Friday morning.

Jeff Masters

Reader Comments

Comments will take a few seconds to appear.

Post Your Comments

Please sign in to post comments.

or Join

Not only will you be able to leave comments on this blog, but you'll also have the ability to upload and share your photos in our Wunder Photos section.

Display: 0, 50, 100, 200 Sort: Newest First - Order Posted

Viewing: 338 - 288

Page: 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19 | 20 | 21 | 22 | 23 | 24 | 25 | 26 | 27 | 28 | 29 | 30 | 31 | 32 | 33 | 34 | 35 | 36 | 37 | 38Blog Index

Quoting Floodman:
Thanks, Doc!

I wanted to address a comment I made to a number of people here from the last blog in particular VAbeachhurricanes:




I agree; we need to consider climatology and the current conditions; not a lock, and no promises, but we're looking at a very possible major outbreak in the tropics sooner than later...2-3 weeks looks plausible, based on anyone of a number of things, but I think Levi32 summed it up very well yesterday in his Tropical Tidbit (sorry, Levi, but that still makes me think of diced pineapple and mango).

That having been said, there's still a chance that the season does go belly up...I think we'd learn more about hurricane forecasting and climatology if it was a bust, but the smart monety is still on some nasties.

What happens here is that people get too caught up in the predictions and not in the chagning environment; when the good ones (StormW and Co start to amend their forecasts based on conditions folks get angry about it...the NASCAR comment was directed at them...weather prediciton is not now, nor is it likely to become anytime soon, an exact science. Listen, pay attention and be prepared, those of you who live close enough to a coast for a hurricane to become a life and death struggle; for the rest of you, "Lighten up, Frances"


Exactly, I am not calling this season a bust, I think activity will pick up, it just will as waves off the coast of africa will begin to hold together as SAL seems to have taken a vacation. Plus what the doctor said as instability coming back to normal once the jet stream moves again. I just hope that it does pick up, if only for the fact people pay attention next time there is predicted to be a bad season. As people who dont follow the weather everyday don't understand the complexity that goes into making these forecasts.
Member Since: Posts: Comments:


Member Since: Posts: Comments:
Terminal Doppler Weather Radar (TDWR)

The Federal Aviation Administration's (FAA) Terminal Doppler Weather Radar (TDWR) system detects and reports hazardous weather in and around airport terminal approach and departure zones. The TDWR identifies and warns air traffic controllers (ATCs) of low altitude wind shear hazards caused by microbursts and their associated gust fronts, in addition to reporting on precipitation intensities and providing advanced warning of wind shifts. The ATCs use the TDWR reports to warn pilots who are potentially affected by the hazardous weather patterns.

Link

These were primarily developed to assist controllers after a number of tragic airliner accidents.

One thing to keep in mind with regard to resolution...WSR-88D (the "normal" weather radars deployed across the USA) can sometimes miss tornados because there resolution is larger than the tornado itself. TDWR has a shorter wavelength, and thus better resolution. However, TDWR does have inherint limitations:

The shorter 5 cm wavelength, which is closer to the size of a raindrop than the 10 cm wavelength, is partially absorbed by precipitation. This is a serious drawback to using TDWR, as the signal can be strongly attenuated in heavy precipitation. This attenuation means that the radar cannot "see" very far through heavy rain and could miss severe weather such as strong thunderstorms which may contain the signature of a tornado, when there is heavy rain falling between the radar and that storm. When heavy rain is falling on the radome, the range of the TDWR is further limited.[1][2] Finally, hail in a thunderstorm scanned by a TDWR can entirely block the signal as its size is larger than the wavelength.[1][2] So a total attenuation behind a storm should raise the possibility of hail in the observer's mind.

A second problem is the smaller non-ambiguous radial velocity or Nyquist velocity. In the case of the TDWR, this means the velocity of precipitations moving at a speed beyond 30 knots away or toward the radar will be analyzed incorrectly because of aliasing. Algorithms to correct for this do not always yield the proper results. NEXRAD has a threshold that is twice as high (62 knots) and thus less processing and interpretation are needed. Because of this, the resolution of radar reflectivity for small scale features such as mesocyclones might be better in TDWR, but the velocity resolution may be worse.

Thus, it is best to use the TDWR in conjunction with a traditional NEXRAD nearby to ensure that nothing is missed.

See Link

v/r

Jon
Member Since: January 7, 2007 Posts: 0 Comments: 40
All World Weather Records at least according to the WMO
Member Since: Posts: Comments:
"....it has been a near-record quiet season." Thanks for the update, Dr. Masters. :)
Member Since: Posts: Comments:
Ahhh, my friends, even a blind squirrel kicks up an acorn every now and again...LOL
Member Since: Posts: Comments:
Quoting Floodman:


You are correct sir!


It was.

Link
Member Since: August 23, 2008 Posts: 7 Comments: 5300
Quoting Floodman:


You are correct sir!


Wow, actually, I was just browsing out of curiosity...I found an article that says that new data was found indicating a 253mph gust in Australia during Olivia. I'm not sure about that...but if it's accurate...good lord.
Member Since: Posts: Comments:
My Muffaletta has joined with my Dixie seems too.
Member Since: Posts: Comments:
Camille is the tightest Storm I can remember to ever strike the US. If you want to see what can happen to people that ignore storm warning read some survivor accounts of that storm.
Member Since: Posts: Comments:
Quoting DestinJeff:
BLOG NEWS ALERT:

"Sniffed out" has been replaced as Blog Word O' the Day by "methinks".

More at 11.


Shall we try for clotpole? As in "Methinks th'art a clotpole?"
Member Since: Posts: Comments:
I see that the CMC has joined with the GFS on a CV system next week.
Member Since: Posts: Comments:
Quoting Floodman:


Well, hell...just call me stumpy! I'll be your test pilot! **shaking my head, LMAO**


Wow I haven't laughed that hard in a LONG time. Okay well since this past Saturday.
Member Since: Posts: Comments:
hey Ike watch out for that potential gfs cv system lol.Where it is now it might pick up a croc and a hippo and dump it in your lake in 3 weeks lol.Hey dont laugh we have had it al on the gulf coast in the last 5 years who knows maybe that model is right and we will have a hypercane from saturn 500mph 80 ft storm surge.After the surge subsides watch for the crocs and hippos ike lol
Member Since: Posts: Comments:
Quoting IKE:


He played basketball at North Carolina in college and played for the Chicago Bulls in the NBA...perhaps the greatest NBA player ever.

He also tried his luck at MLB for a short period of time, but came back to the NBA after that failed.


Right, I know he's a famous NBA player but didn't know he left and came back lol.
Member Since: Posts: Comments:
Quoting GBguy88:


Iniki produced a gust to 227mph, and then the instrument failed. I think the strongest non-tornadic wind gust is 231mph on Mount Washington.


You are correct sir!
Member Since: Posts: Comments:
Quoting Floodman:


These are sustained:

1969 - Camille - 190 mph sustained winds
1980 - Allen - 190 mph sustained winds

1950 - Dog - 185 mph sustained winds

1980 - Gilbert - 185 mph sustained winds

2005 - Wilma - 185 mph sustained winds


It is said tha the Labor Day cane produced a one minute sustain of 210, but no one can verify and that's a little too convenient to be anything but apocryphal


Iniki produced a gust to 227mph, and then the instrument failed. I think the strongest non-tornadic wind gust is 231mph on Mount Washington.
Member Since: Posts: Comments:
Quoting msgambler:
I agree flood. And as for gusts, we could have stood in between a couple of buildings in Gulfport, MS during Camille and gotten 240 mph probably. So the mountianside gust hold no water, or wind, in my books.


Yep...I believe the regs say in the flat, in the open, at about 3 metres, yes?
Member Since: Posts: Comments:
It should be a Tropical Depression...

Member Since: Posts: Comments:
Quoting TexasGulf:


Fastening down the anemometer for 200+ mph wind speeds is doable, but making the structural anchoring and housing impact resistant would be a challenge. That's why I would prefer to make a 'hand-held' model.

You wouldn't have to put your entire body into the 200 mph wind field, just your hand. Of course, you realize that impact damage voids the warranty.


Well, hell...just call me stumpy! I'll be your test pilot! **shaking my head, LMAO**
Member Since: Posts: Comments:
316. IKE
Quoting Levi32:


MJ?


He played basketball at North Carolina in college and played for the Chicago Bulls in the NBA...perhaps the greatest NBA player ever.

He also tried his luck at MLB for a short period of time, but came back to the NBA after that failed.
Member Since: June 9, 2005 Posts: 23 Comments: 37858
Quoting CosmicEvents:
Wasn't the long range GFS showing a major cyclone hitting the Gulf Coast 14 days out....14 days ago? I'm looking, but I don't see one there.


Hmmm...methinks thou dost protest too much; calling anything making a Gulf Coast landfall at 14 days is pretty damned inmpressive if you ask me, especially given no one would expect much by way of accuracy on the intensity side of things...
Member Since: Posts: Comments:
Quoting Floodman:


Don't forget the fastening it to the ground part, vis a vis, the anemometer at Slidell Airport during a recent hurricane whose name is used far too often here


Fastening down the anemometer for 200+ mph wind speeds is doable, but making the structural anchoring and housing impact resistant would be a challenge. That's why I would prefer to make a 'hand-held' model.

You wouldn't have to put your entire body into the 200 mph wind field, just your hand. Of course, you realize that impact damage voids the warranty.
Member Since: Posts: Comments:
Quoting StormW:
Do ya think that the stronger A/B high we've had in the past few weeks may be a contributor to the lack of instability?


Interesting to think about Storm, would make some sense to a weather newbie like myself. If the pressure reading is higher then normal, wouldnt that make the pressure expand out farther, and increase stability? I think it does this on land somewhat as well, but not sure on the oceans.
Member Since: Posts: Comments:
Quoting Levi32:


It's higher resolution than normal NEXRAD. Great for tracking supercells if they are in range. They're great for observing the details of a hurricane's eyewall as well. The downside is they have a very small range, which is why they are only useful for such events and not that great for daily use.


Thanks Levi!
Member Since: Posts: Comments:
NEXSAT African Overview
Member Since: Posts: Comments:
Quoting Floodman:


These are sustained:

1969 - Camille - 190 mph sustained winds
1980 - Allen - 190 mph sustained winds

1950 - Dog - 185 mph sustained winds

1980 - Gilbert - 185 mph sustained winds

2005 - Wilma - 185 mph sustained winds


It is said tha the Labor Day cane produced a one minute sustain of 210, but no one can verify and that's a little too convenient to be anything but apocryphal
I agree flood. And as for gusts, we could have stood in between a couple of buildings in Gulfport, MS during Camille and gotten 240 mph probably. So the mountianside gust hold no water, or wind, in my books.
Member Since: Posts: Comments:
Quoting ElConando:
212mph! My goodness. Is that the highest recorded gust from a land falling cane in America? Anyone know?


These are sustained:

1969 - Camille - 190 mph sustained winds
1980 - Allen - 190 mph sustained winds

1950 - Dog - 185 mph sustained winds

1980 - Gilbert - 185 mph sustained winds

2005 - Wilma - 185 mph sustained winds


It is said tha the Labor Day cane produced a one minute sustain of 210, but no one can verify and that's a little too convenient to be anything but apocryphal
Member Since: Posts: Comments:
Quoting ElConando:


It can show tornadoes? how so?


It's higher resolution than normal NEXRAD. Great for tracking supercells if they are in range. They're great for observing the details of a hurricane's eyewall as well. The downside is they have a very small range, which is why they are only useful for such events and not that great for daily use.
Member Since: Posts: Comments:
Quoting Levi32:


MJ?


Michael Jordan.
Member Since: Posts: Comments:
Quoting ElConando:


Second coming? Like MJ?


MJ?
Member Since: Posts: Comments:
Quoting pcola57:


Flood you kill me..LOL


It was interesting evening on the east coast of Florida in 2004...fortunately I had a good calm place to collect myself after the attempt

LOL
Member Since: Posts: Comments:
Quoting IKE:
To those that accuse me of only posting models that show nothing....12Z CMC...


12Z NOGAPS through 180 hours...


LOL. I know u wont post the gfs
Member Since: Posts: Comments:
Quoting Levi32:


Not when there are tornadoes.


It can show tornadoes? how so?
Member Since: Posts: Comments:
Quoting KEEPEROFTHEGATE:
Ibelieve 227mph was recorded in cuba not so long ago but it may have been higher cause the recorder stopped at that point i bet it would be safe to say it was blown away

Link
Member Since: Posts: Comments:
(becomes near invest near the CV Islands on the 19)

sorry I meant near TD near the CV Islands on the 19
Member Since: Posts: Comments:
Quoting SAINTHURRIFAN:
Destin jeff did you see anything in Masters blog that he thinks this pattern will change soon? Im just a dumb old MBA major but i did not see him state although this will soon change.On the other note when i came on this morning all everyone was talking about was td 5 taking a loop back into the gulf.Now some one post a month a way model run thats at between 10 and 20 east. lol i thought he said 10 to 20 west that i might could look at.But come on 10 to 20 east? has this season been that disappointing that we are hanging hopes on a model running that far out and away?Not picking or starting a argument but those continued statements is what causes people to call some on here wishcasters they bring it on themselves.In closing the gfs is the same model that predicted this morning td5 to be a hurrricane next week you see what dr masters thought about that.lets let these phantom systems actually show up before we start posting and worrying about something that has not happened.this is not downcasting its present casting and at the present thier is no tropical system in the eastern atlantic.I know alot will disagree with this post just hope it gives some a little something to think about.


LOL! Presentcasting. I knew I missed my calling. Just imagine the lifetime skill scores. Alas--The lack of challenge would have killed me though.
Member Since: Posts: Comments:
Quoting KEEPEROFTHEGATE:
Ibelieve 227mph was recorded in cuba not so long ago but it may have been higher cause the recorder stopped at that point i bet it would be safe to say it was blown away


Gustav had that wind reading, it was from the wind going down the side of a mountain and the anemometer was at the bottom of the mountain.
Member Since: Posts: Comments:
Quoting Levi32:
CMC picking up on possible 2nd coming of TD 5 as well.


Second coming? Like MJ?
Member Since: Posts: Comments:
Quoting CosmicEvents:
Wasn't the long range GFS showing a major cyclone hitting the Gulf Coast 14 days out....14 days ago? I'm looking, but I don't see one there.


bogus-cane
Member Since: Posts: Comments:
Wasn't the long range GFS showing a major cyclone hitting the Gulf Coast 14 days out....14 days ago? I'm looking, but I don't see one there.
Member Since: Posts: Comments:
12Z CMC Hour 144:

Member Since: Posts: Comments:
Quoting Floodman:


Does that take into account the speed of the person holding it? I tried to stand up in 100mph once...only very briefly, but I can honestly say I tried...


Flood you kill me..LOL
Member Since: Posts: Comments:
293. Jax82
I have a feeling that in a month we'll completely forget how inactive the beginning of this season has been in comparison to predictions. It only takes one big one to make a season a bad one.
Member Since: Posts: Comments:
Latest UKMET Office 3 East Pacific, 2 Atlantic
Member Since: Posts: Comments:
Quoting Patrap:
Never used TDWR..

it sucks as a radar tool..


Exactly my point.
Member Since: Posts: Comments:
Quoting Snowfire:

It will stay elusive until we develop a 225mph anemometer


There are plenty of those, even airspeed indicators for supersonic aircraft. The real trick is to make it wave-, surge-, and shrapnel-proof.


Don't forget the fastening it to the ground part, vis a vis, the anemometer at Slidell Airport during a recent hurricane whose name is used far too often here
Member Since: Posts: Comments:
Quoting Patrap:
Never used TDWR..

it sucks as a radar tool..


Not when there are tornadoes.
Member Since: Posts: Comments:
according to the 12Z GFS run

starts a low level invest over W africa moves west on the 18 of Aug

low level invest comes off the coast of Africa and develops further

becomes near invest near the CV Islands on the 19

becomes a TD by miday on the 19 near the CV Islands

the TD upgraded to TS on the 20 west of the CV Islands

weakens slightly to weak TS/strong TD on the 21

get stronger to a strong TS on the 23

becomes a hurricane just east of the Leewards Is on the 24

continues hurricane status as it moves WNW-NW there after


I got a feeling that if this system forms it will not go that far north I think that it would be somewhere near 70-75W befor making it WNW-NW movements
Member Since: Posts: Comments:

Viewing: 338 - 288

Page: 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19 | 20 | 21 | 22 | 23 | 24 | 25 | 26 | 27 | 28 | 29 | 30 | 31 | 32 | 33 | 34 | 35 | 36 | 37 | 38Blog Index

Top of Page

About JeffMasters

Jeff co-founded the Weather Underground in 1995 while working on his Ph.D. He flew with the NOAA Hurricane Hunters from 1986-1990.